OMG! Thanks for posting your STM and those awesome pictures. Just wow...

Speechless... :-)

Thanks for the follow!

Hi Dan, thank you for the follow and like.

You're welcome, nice job on packing lots of functionality in a compact instrument, and the software looks nice too! And thanks for following my STM!

It's a good point. Actually there are several areas of this project that will benefit from feedback. The one that I may attack first is temperature control of the laser diode. It turns out that relatively small temperature fluctuations affect the diode mode/wavelength and this is the most serious stability issue at present. There is a reason that industrial tools use a HeNe laser in their interferometers!

Hmm yeah that's a good point. With a peltier and thermistor on the laser diode (in a closed box), with an analog PI controller, you should be able to get extremely good temperature stability.

Nice collection of physics/science related projects here. Thank you for following my interferometers.

Thanks! The interferometer projects are very cool! It might be neat to close the loop between the photodiode and voice coil with a simple PI loop. You could then read off sub-wavelength displacements from the control voltage sent to the coil, and the response would be linear.